%0 Journal Article
%T Soil Microarthropods in a Secondary Rainforest, Rivers State, Nigeria - IV- The Impact of Oil Pollution on Their Vertical Distribution
%J Resources and Environment
%@ 2163-2634
%D 2012
%I 
%R 10.5923/j.re.20120202.03
%X Studies were undertaken, May, 2007-April, 2009, to document species richness, bioindicator species, abundance, density, vertical distribution, etc. of soil microarthropods (mites, collembolans) in unpolluted and polluted habitats in a secondary rainforest, Rivers State, Nigeria. This paper focuses on the effects of oil pollution on the vertical distribution of these mesofauna. Sampling was effected monthly by a bucket-type auger to a depth of 15.0cm in four habitat-types (unpolluted, polluted by oil spills approximately 1yr, 3yrs and 6yrs pre-study). The modified Bukard model of the Berlese-Tullgren funnel was used for extraction. Identifications were undertaken using standard keys and unidentified specimens were compared to type specimens. In the unpolluted and polluted (3 and 6yrs pre-study) habitats, there was an inverse relationship between mite/ collembolan abundance/density (except in the Prostigmata) and soil depth; however, the correlations were not significant. In contrast, there was a significant direct correlation between mite abundance/density and depth in the habitat, polluted 1yr pre-study (F=29.11; df=1.3; p<0.05). In the unpolluted habitat, approximately 80% of all mites and 90% of collembolans were collected within the range 0.00-10.0cm. In the habitat, polluted 1yr pre-study, no mites were collected above a depth of 5.0cm and 70% were found below 10.0cm. In the habitats, polluted 3 and 6yrs pre-study, approximately all mites were found above a depth of 10.0cm. There were direct relationships between collembolan densities and soil depths in the two habitat-types (polluted 1 and 3 yrs pre-study) but the correlations were not significant (F=6.22; df= 1.3; p> 0.05). In the unpolluted habitat, approximately 90% of all collembolans were found above a depth of 10.0cm; this declined to 30% in the habitat, polluted 1yr pre-study, and rose to 50% and 85% in the habitats, polluted 3 and 6yrs pre-study.
%K Soil Microarthropods
%K Oil Pollution
%K Effects
%K Vertical Distribution
%U http://article.sapub.org/10.5923.j.re.20120202.03.html